Roman Returns in the Middle of 'Chicago Fire's Call in 'P.D.' Crossover (PHOTOS)

Meredith Jacobs

Welcome back to the One Chicago universe, Brian Geraghty.

The actor reprises his role as Sean Roman — but he's no longer a cop — in an upcoming Chicago Fire/P.D. crossover on Wednesday, February 26. And this case is going to be quite personal for him because he's looking for his sister.

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The star also previews Roman's return to the One Chicago universe in a February 'P.D.' crossover.

"We go into a big fire just to do our job, and all of a sudden, Roman runs out and that brings us all together and we try to help him," Fire's Joe Minoso teased.

Click through the gallery above for a look at Roman's surprise appearance during a Fire call, his reunion with Burgess (Marina Squerciati) over on P.D., and more.

Chicago Fire-P.D. Crossover, Wednesday, February 26, 9/8c, NBC